POSTOPERATIVE CHEMOTHERAPY IN CHILDREN LESS-THAN 4 YEARS OF AGE WITH MALIGNANT BRAIN-TUMORS - PROMISING INITIAL RESPONSE TO A VETOPEC-BASEDREGIMEN - A STUDY OF THE AUSTRALIAN AND NEW-ZEALAND CHILDRENS-CANCER-STUDY-GROUP (ANZCCSG)

Purpose: Postoperative chemotherapy with indefinite postponement of ra diation therapy in children <4 years old with brain tumors was investi gated in a multi-institutional study. Patients and Methods: From 1991 to 1995, 42 patients aged 3 to 47 months (median 20) with brain tumors were enrolled in a 2-phase chemotherapy protocol: 16 patients had med ulloblastoma (MB); 8 had supratentorial primitive neuroectodermal tumo r (PNET); 14 had ependymoma; and 4 had other tumors. The initial phase was comprised of 4 courses of the 3-drug regimen: vincristine (VCR), etoposide (VP-16), and intensive cyclophosphamide (CPA) in a previousl y reported schedule (VETOPEC). The continuation phase was comprised of 2-drug courses: A, CPA + VCR; B, cisplatin + VP-16; and C, carboplati n + VP-16, for a total duration of 64 weeks. Results: Response to VETO PEC was evaluable in 28 patients with postresection residual (25) and/ or metastatic (1 M2, 6 M3) tumor. There were 9 complete responses (CR) and 9 partial responses (PR) with a combined CR + PR of 64% (95% conf idence interval [CI] 44 to 81). In 12 evaluable patients with MB, CR PR was 82% (48 to 98); in 6 patients with PNET, 50% (12 to 88); and, in 8 patients with ependymoma, 86% (42 to 99). Of 40 patients eligible for further analysis, 6 remain progression-free at a median of 30 mon ths, 14 are alive at a median of 38 months, 29 have progressed at a me dian of 7 months (range, 2 to 37 months), and 26 have died. The progre ssion-free and overall survival rates at 36 months are estimated to be 11% (95% CI 1 to 22) and 34% (18 to 50), respectively.Conclusions: Th e initial response to the VETOPEC regimen is encouraging and warrants study of further dose escalation. Survival remains poor with current s trategies in this high-risk population.